java编写的简易计算器

主要用了2个类来实现的&＃xff0c;话不多说&＃xff0c;直接看运行结果&＃xff0c;然后在奉上源代码

1.Index.java

import java.awt.Color;
import java.awt.Container;
import java.awt.Font;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;import javax.swing.*;public class Index extends JFrame implements ActionListener {private int choice &＃61; 0;private double a &＃61; 0;private double b &＃61; 0;private double c &＃61; 0;private boolean next &＃61; true;public JButton one &＃61; new JButton("1");public JButton two &＃61; new JButton("2");public JButton three &＃61; new JButton("3");public JButton four &＃61; new JButton("4");public JButton five &＃61; new JButton("5");public JButton six &＃61; new JButton("6");public JButton seven &＃61; new JButton("7");public JButton eight &＃61; new JButton("8");public JButton nine &＃61; new JButton("9");public JButton zero &＃61; new JButton("0");public JButton point &＃61; new JButton(".");public JButton add &＃61; new JButton("&＃43;");public JButton subtract &＃61; new JButton("-");public JButton mult &＃61; new JButton("*");public JButton divi &＃61; new JButton("/");public JButton equal &＃61; new JButton("&＃61;");public JButton clean &＃61; new JButton("C");public JTextField message &＃61; new JTextField();public JTextField result &＃61; new JTextField();public JFrame jf &＃61; new JFrame("计算器");public Container con &＃61; jf.getContentPane();public Font font &＃61; new Font("楷体", 0, 15);public Font font1 &＃61; new Font("楷体", 0, 20);Index() {jf.setBounds(90, 90, 250, 220);jf.setResizable(false);jf.setVisible(true);jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);jf.setResizable(false);jf.setLocationRelativeTo(null);message.setBounds(5, 5, 185, 15);message.setBorder(null);message.setBackground(Color.white);message.setFont(font);message.setEditable(false);result.setBounds(5, 20, 185, 25);result.setBorder(null);result.setBackground(Color.white);result.setFont(font1);result.setEditable(false);//设置为不可写&＃xff0c;即只读clean.setBounds(195, 5, 45, 40);clean.setFont(font);clean.addActionListener(this);one.setBounds(5,50,50,30);one.setFont(font);one.addActionListener(this);two.setBounds(60,50,50,30);two.setFont(font);two.addActionListener(this);three.setBounds(120,50,50,30);three.setFont(font);three.addActionListener(this);add.setBounds(180, 50, 60, 30);add.setFont(font);add.addActionListener(this);four.setBounds(5,85,50,30);four.setFont(font);four.addActionListener(this);five.setBounds(60,85,50,30);five.setFont(font);five.addActionListener(this);six.setBounds(120,85,50,30);six.setFont(font);six.addActionListener(this);subtract.setBounds(180, 85, 60, 30);subtract.setFont(font);subtract.addActionListener(this);seven.setBounds(5,120,50,30);seven.setFont(font);seven.addActionListener(this);eight.setBounds(60,120,50,30);eight.setFont(font);eight.addActionListener(this);nine.setBounds(120,120,50,30);nine.setFont(font);nine.addActionListener(this);mult.setBounds(180, 120, 60, 30);mult.setFont(font);mult.addActionListener(this);point.setBounds(5,155,50,30);point.setFont(font);point.addActionListener(this);zero.setBounds(60,155,50,30);zero.setFont(font);zero.addActionListener(this);equal.setBounds(120,155,50,30);equal.setFont(font);equal.addActionListener(this);divi.setBounds(180, 155, 60, 30);divi.setFont(font);divi.addActionListener(this);con.setLayout(null);//不用默认的布局方式&＃xff08;布局管理器&＃xff09;con.setVisible(true);con.add(message);con.add(result);con.add(clean);con.add(one);con.add(two);con.add(three);con.add(add);con.add(four);con.add(five);con.add(six);con.add(subtract);con.add(seven);con.add(eight);con.add(nine);con.add(mult);con.add(point);con.add(zero);con.add(equal);con.add(divi);}private static void hint(String str) {JOptionPane.showMessageDialog(null, str, "提示", JOptionPane.INFORMATION_MESSAGE);}private void clean(String str) {this.message.setText(str);this.result.setText("");}public void actionPerformed(ActionEvent e) {if(e.getSource() &＃61;&＃61; this.one) {if(next) {clean("");this.next &＃61; false;}this.result.setText(result.getText()&＃43;"1");}else if(e.getSource() &＃61;&＃61; this.two) {if(next) {clean("");this.next &＃61; false;}this.result.setText(result.getText()&＃43;"2");}else if(e.getSource() &＃61;&＃61; this.three) {if(next) {clean("");this.next &＃61; false;}this.result.setText(result.getText()&＃43;"3");}else if(e.getSource() &＃61;&＃61; this.four) {if(next) {clean("");this.next &＃61; false;}this.result.setText(result.getText()&＃43;"4");}else if(e.getSource() &＃61;&＃61; this.five) {if(next) {clean("");this.next &＃61; false;}this.result.setText(result.getText()&＃43;"5");}else if(e.getSource() &＃61;&＃61; this.six) {if(next) {clean("");this.next &＃61; false;}this.result.setText(result.getText()&＃43;"6");}else if(e.getSource() &＃61;&＃61; this.seven) {if(next) {clean("");this.next &＃61; false;}this.result.setText(result.getText()&＃43;"7");}else if(e.getSource() &＃61;&＃61; this.eight) {if(next) {clean("");this.next &＃61; false;}this.result.setText(result.getText()&＃43;"8");}else if(e.getSource() &＃61;&＃61; this.nine) {if(next) {clean("");this.next &＃61; false;}this.result.setText(result.getText()&＃43;"9");}else if(e.getSource() &＃61;&＃61; this.zero) {if(next) {clean("");this.next &＃61; false;}this.result.setText(result.getText()&＃43;"0");}else if(e.getSource() &＃61;&＃61; this.point) {this.result.setText(result.getText()&＃43;".");this.next &＃61; false;//}else if(e.getSource() &＃61;&＃61; this.add) {//加String number &＃61; this.result.getText();String str &＃61; this.message.getText() &＃43; this.result.getText() &＃43; "&＃43;";if(number.equals("")){hint("请输入数据&＃xff01;");return;}a &＃61; Double.parseDouble(number);this.choice &＃61; 1;this.message.setText(str);this.result.setText("");this.next &＃61; false;}else if(e.getSource() &＃61;&＃61; this.subtract) {//减String number &＃61; this.result.getText();String str &＃61; this.message.getText() &＃43; this.result.getText() &＃43; "-";if(number.equals("")){this.result.setText("-");}else{a &＃61; Double.parseDouble(number);this.choice &＃61; 2;this.message.setText(str);this.result.setText("");}this.next &＃61; false;}else if(e.getSource() &＃61;&＃61; this.mult) {//乘String number &＃61; this.result.getText();String str &＃61; this.message.getText() &＃43; this.result.getText() &＃43; "*"&＃43; "";if(number.equals("")){hint("请输入数据&＃xff01;");return;}a &＃61; Double.parseDouble(number);this.choice &＃61; 3;this.message.setText(str);this.result.setText("");this.next &＃61; false;}else if(e.getSource() &＃61;&＃61; this.divi) {//除String number &＃61; this.result.getText();String str &＃61; this.message.getText() &＃43; this.result.getText() &＃43; "/";if(number.equals("")){hint("请输入数据&＃xff01;");return;}a &＃61; Double.parseDouble(number);this.choice &＃61; 4;this.message.setText(str);this.result.setText("");this.next &＃61; false;}else if(e.getSource() &＃61;&＃61; this.equal){String number &＃61; this.result.getText();if(number.equals("")){hint("请输入数据&＃xff01;");return;}b &＃61; Double.parseDouble(number);if(b &＃61;&＃61; 0 && choice &＃61;&＃61; 4) {hint("除数不能为0&＃xff01;");clean("");return;}String str &＃61; this.message.getText() &＃43; this.result.getText() &＃43; "&＃61;";this.message.setText(str);c &＃61; Counter.compute(a,b,choice);String re &＃61; new String();re &＃43;&＃61; c;int L &＃61; re.length();if(re.charAt(L-2) &＃61;&＃61; &＃39;.&＃39; && re.charAt(L-1) &＃61;&＃61; &＃39;0&＃39;) re &＃61; re.substring(0, L-2);this.result.setText(re);this.next &＃61; true;}else if(e.getSource() &＃61;&＃61; this.clean) {clean("");}}}


2.Counter.java

public class Counter {public static void main(String[] args) {new Index();}public static double compute(double a, double b, int choice) {double c &＃61; 0;switch(choice) {case 1: c &＃61; a &＃43; b;break;case 2: c &＃61; a - b;break;case 3: c &＃61; a * b;break;case 4: c &＃61; a / b;break;}
//System.out.println(c);return c;}}